Carotid cave aneurysm (coiled) and MCA fenestration


Carotid cave aneursyms have a complex relationship to the dura, and it is difficult to determine on imaging if they intra or extradural. Their neck is considered intradural and in general they are thus thought to present a risk for subarachnoid hemorrhage (which purely extradural cavernous sinus aneurysms do not).